<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style type="text/css">
	body{
		background: #eee;
	}
	#box{
		width: 0px;
		height: 0px;
		font-size: 0;
		border: 30px dashed transparent;/*兼容性的写法solid在ie6下不兼容*/
		border-top: 30px solid purple;/*用solid是兼容性的写法*/
	}
</style>
</head>

<body>

<div id="box"></div>


</body>
</html>
